Door latch

ABSTRACT

A door latch or lock to be mounted on a door having an opening therethrough adjacent one edge and having a hole in such edge into the opening, comprising two escutcheon members respectively insertable into and adapted to overlie the ends of the opening through the door, two knobs respectively mounted on the escutcheon members, a latchbolt housing insertable into the hole in the door edge and containing a latchbolt, and means connected to the knobs for retracting the latchbolt. The latchbolt housing and the escutcheon members interlock, and a single screw coaxial with the knob axis interconnects the escutcheon members to secure the escutcheon members and the latchbolt housing in assembled relation. The knobs are merely snapped into place in rotatably mounting them on the excutcheon members. The device may be used either as a simple door latch capable of being opened by rotating either knob, or it may be used as a door lock which can be locked from one side and which can be unlocked from the other side in an emergency. With two or three exceptions, all of the parts of the device are made of plastic materials, the external surfaces of the exposed parts being suitably finished.

United States Patent [72] Inventor Philip R. Morgan Monrovia, Calif. 21Appl. No. 823,839 [22] Filed May 12, 1969 [45] Patented May25, 1971 [73]Assignee Acme Appliance Manufacturing Company Monrovia, Calif.

[54] DOOR LATCH 8 Claims, 10 Drawing Figs.

[52] U.S.Cl 292/169, 292/336.3, 292/353, 292/357, 292/359 [51] Int. ClE05b 3/06, EOSb 9/08, 1505b 15/16 [501 Field otSearch 292/169, 337, 340,353, 359, (PLP), 356, 357, 336.3, 358; 70/451,147,152

[56] References Cited UNITED STATES PATENTS 181,705 8/1876 Niles 292/357506,461 10/1893 Beckwith. v292Il69.2l 1,826,093 10/1931 Schlage292/l69.22 2,512,814 6/1950 Solovieffet a1. 292/359 7 2,795,445 6/1957Beil 1 1963 Patriquin et a1.

Primary ExaminerStephen J. Novosad Assistant ExaminerAlbert G. Craig, JrAltomeyl-larris, Kiech, Russell and Kern ABSTRACT: A door latch or lockto be mounted on a door having an opening therethrough adjacent one edgeand having a hole in such edge into the opening, comprising twoescutcheon members respectively insertable into and adapted to overliethe ends of the opening through the door, two knobs respectively mountedon the escutcheon members, a latchbolt housing insertable into the holein the door edge and containing a latchbolt, and means connected to theknobs for retracting the latchbolt. The latchbolt housing and theescutcheon memtiers interlock, and a single screw coaxial with the knobaxis interconnectsthe escutcheon members to secure the escutcheonmembers and the latchbolt housing in assembled relation. The knobs aremerely snapped into place in rotatably mounting them on the excutcheonmembers. The device may be used either as a simple door latch capable ofbeing opened by rotating either knob, or it may be used as a door lockwhich can be locked from one side and which can be unlocked from theother side in an emergency. With two or three exceptions, all of theparts of the device are made of plastic materials, the external surfacesof the exposed parts being suitably finished.

PATENTEUMAYZSISYI 3580.622

SHEET 1 UF 3 INVENTOR PH/ 6 Maze/W noon LATCH BACKGROUND OF THEINVENTION The present invention relates in general to door latches orlocks and, more particularly, to a device to be mounted on a door havingan opening therethrough adjacent one edge and having a hole in such edgeinto the opening, comprising: two escutcheon members respectivelyinsertable into and adapted to overlie the ends of the openings throughthe door and providing a knob axis; a latchbolt housing containing alatchbolt and insertable into the hole in the door edge; two knobsrespectively mounted on the escutcheon members for rotation about theknob axis; and means connected to the knobs for retracting the latchboltin opposition to the action of a spring biasing same into an extendedposition for engagement with a latch or strike plate mounted on adoorjamb.

SUMMARY AND OBJECTS OF THE INVENTION A primary object of the inventionis to provide a latch of the foregoing nature having a single connectingmeans on the knob axis for interconnecting the escutcheon members.

More particularly, a primary object of the invention is to provide adevice wherein the escutcheon-member-interconnecting means comprises asingle screw coaxial with the knob axis, such screw being carried by andhaving a head engaging one of the escutcheon members and beingthreadable into the other escutcheon member. 7

An important object of the invention is to provide a door latch or lockwhich includes interengageable means on the escutcheon members and thelatchbolt housing for interlocking these components in assembledrelation.

With the foregoing construction, since the escutcheon members and thelatchbolt housing are interlocked, the single screw for interconnectingthe two escutcheon members acts to secure the escutcheon members and thelatchbolt housing together in assembled relation. This is an importantfeature of the invention since it avoids the necessity for pluralscrews, or the like, to secure the escutcheon members together, or tosecure them to the door, and to secure the latchbolt housing to thedoor. With the present invention, a single screw performs all of thesefunctions.

Another important object of the invention is to provide snap-actinglatching means integral with the escutcheon members and the knobs forrotatably connecting the knobs to the escutcheon members. With thisconstruction, the knobs are merely snapped into place in the escutcheonmembers to facilitate assembly, which is an important feature.

Another object is to provide a door latch or lock wherein thesnap-acting latching means for the knobs include integral, shouldered,flexible latching tongues on the knobs paralleling the knob axis andengageable with complementary, integral shoulders on the escutcheonmembers, and wherein the latchbolt retracting means includes a pinparalleling the knob axis and extending through the knob latchingtongues to reinforce and stiffen same.

Still another object of the invention is to provide a device which maybe used as a door lock to achieve privacy. In this connection, an objectis to provide a device wherein one of the knobs is axially movablerelative to its escutcheon member, and wherein a locking means on suchknob and its escutcheon member responds to axially inward movement ofthis knob to lock both knobs against rotation so as to preventretraction of the latchbolt. A further object in this setting is toprovide means carried by the other knob, and accessible from theexterior thereof in an emergency, for moving the first knob axiallyoutwardly to release its locking means so that both knobs can be rotatedto permit retraction of the latchbolt.

Yet another object of the invention is to provide a device wherein thelatchbolt housing may be installed in its hole in the door edge with thelatchbolt facing in either direction, depending. on which way the doorswings, and wherein the latchbolt is provided with oppositely extendinglugs either of which is engageable by the latchbolt-retracting pininterconnecting the two knobs, the pin engaging one lug in one angularposition of the latchbolt housing and engaging the other lug in theother angular position thereof.

The foregoing objects, advantages, features and results of the presentinvention, together with various other objects, advantages, features andresults which will be evident to those skilled in the door latch or lockart in the light of this disclosure, may be achieved with the exemplaryembodiment of the invention described in detail hereinafter andillustrated in the accompanying drawings.

DESCRIPTION OF DRAWINGS In the drawings:

FIG. 1 is an exploded perspective view on a reduced scale showing a doorlock or lock set which embodies the invention;

FIG. 2 is a sectional view taken as indicated by the arrowed line 2-2 ofFIG. 1, except that the lock is shown installed with all of itscomponents shown in their actual relative positions;

FIG. 3 is a sectional view taken as indicated by the arrowed line 3-3 ofFIG. 2;

FIG. 4 is a sectional view taken as indicated by the arrowed line 4-4 ofFIG. 3;

FIGS. 5, 6 and 7 are sectional views respectively taken along thearrowed lines 5-5, 6-6 and 7-7 of FIG. 4;

FIG. 8 is a view similar to FIG. 4, but showing the door lock of theinvention locked from the inside and showing how it can be unlocked fromthe outside in an emergency;

FIG. 9 is a sectional view taken approximately as indicated by thearrowed line 9-9 of FIG. 3; and

FIG. 10 is a view similar to FIG. 3, but showing a latchbolt of thedevice in its retracted position.

DESCRIPTION OF EXEMPLARY EMBODIMENT OF INVENTION Illustrated in thedrawings is a door lock or lock set 20 of the invention which, as willbe explained, can be locked from one side for privacy. As will also beexplained, the lock 20, with a very few minor modifications, can be usedas a simple door latch.

More particularly, the door lock 20 is adapted to be mounted on a door22 having an opening 24 therethrough adjacent the vertical edge 26opposite the hinged edge, not shown, of the door. The door edge 26 has ahole 28 perpendicular to and communicating with the opening 24. When thedoor 22 is closed, its edge 26 registers with a jamb 30 having a cavity32 therein. Various parts of the lock 20 are installed in the opening24, the hole 28 and the cavity 32. These are all simple bores ofcircular cross section and represent the only preparations of the door22 and the jamb 30 required for installation of the lock 20. In otherwords, only simple boring operations are required, no mortisingoperations, or the like, being necessary.

The door lock 20 includes as its primary components the following:inside and outside escutcheon members 34 and 36 respectively insertedinto and overlying the ends of the open ing 24 on the inside and theoutside, respectively, of the door 22, the escutcheon members providinga knob axis 38; a single connecting means 40 coaxial with the knob axisand interconnecting the escutcheon members; inside and outside knobs 44and 46 respectively rotatably mounted on the inside and outsideescutcheon members for rotation about the knob axis; a housing 48 for aspring-extended latch bolt 50 inserted into the hole 28 in the door edge26 and interlocked with the escutcheon members; means 52 interconnectingthe knobs and engaging the latchbolt for retracting same; and a latchplate 54 inserted into the cavity 32 in the jamb 30 and receivinglatchbolt in its extended position.

When installing the door lock 20, the subassembly comprising thelatchbolt 50 and its housing 48 must be installed first. Consequently,this subassembly will be considered first for convenience.

The latchbolt housing 48 is substantially cylindrical and is provided atits outer end with an external annular flange 56. This flange isrelatively small and tapers outwardly to a sharp edge. lnwardly of theflange 56 are circumferentially spaced, longitudinal ribs 58 which alsotaper outwardly to sharp edges. ln installing the latchbolt housing 48and the parts contained therein, it is merely necessary to tap on theouter end of this subassembly with an ordinary hammer to drive thelatchbolt housing into its hole 28, continuing this driving operationuntil the flange 56 seats itself, as shown, for example, in FIGS. 2, 3and 10. During this driving process, the ribs 58 cut their own groovesin the wall of the hole 28. Thus, no mortising operation is necessary.

The latchbolt 50 has a flat longitudinal side 60 which must be sopositioned that it faces the inside of the door 22. Thus, a beveled face62 of the latchbolt 50 faces the outside of the door.

The latch plate 54 is complementary to the latchbolt 50, as perhaps bestshown in FIG. 2, and must be complementarily oriented angularly in acavity 32 in the jamb 30. The latch plate 54 also has circumferentiallyspaced, longitudinally extending, sharp-edged, external ribs 64 whichform their own grooves in the wall of the cavity when the latch plate isdriven in a manner similar to the latchbolt housing 48. Thus, nomortising operations are required. Also, no screws for securing thelatch plate are necessary. The latch plate 54 is provided with a strikerportion66 which is engageable by the latch bolt 50 and which overliesthe surface of the jamb 30 adjacent the cavity 32.

The latchbolt 50 is provided therein with a central longitudinal slot68, FIGS. 2, 3 and 10, containing a coiled compression spring 70 seatedat one end against a spring seat 72 on the latchbolt and at its otherend against'a spring seat 74 on the latchbolt housing. As will beapparent, the spring 70 biases the latchbolt 50 toward its extendedposition, movement in this direction being limited by engagement of atransverse stop web 76 on the latchbolt with the spring seat 74 on thelatchbolt housing, as best shown in F IG. 2.

Referring particularly to FIGS. 3 and 10, the latchbolt 50 is providedat its inner or rearward end with two hooklikelugs 78 on opposite sidesthereof, i.e., angularly spaced apart by 180. Either of these lugs 78may be engaged by a latchboltretracting pin 80 constituting thelatchbolt-retracting means 52, depending upon the angular orientation ofthe latchbolt housing 48 when it is driven into the hole 28 in the dooredge 26. Thus, as will be apparent, the latchbolt subassembly may beinstalled in either of two positions angularly spaced 180 apart,depending on which way the door 22 swings, it being understood that thebeveled face 62 of the latchbolt 50 must face in the direction ofclosing movement of the door. In one angular orientation of thelatchbolt subassembly, the retracting pin 80 engages one of the lugs 78.in the other angular orientation of the latchbolt subassembly, theretracting pin 80 engages the other lug. Thus, the latchbolt subassemblyis reversible so that the lock will accommodate either lefthand orright-hand doors.

Turning now to the escutcheon members 34 and 36, they respectivelyinclude external annular rosette flanges 84 and 86 seated against theinner and outer sides of the door 22 around the inner and outer ends ofthe opening 24 therethrough. The escutcheon members 34 and 36 alsorespectively include central hubs 88 and 90 the inner ends of which areencircled by skirts 92 and 94. Radial webs interconnect thecorresponding skirts and hubs.

The escutcheon member 34 includes two longitudinally extending,diametrically opposed posts 96 insertable into complementary sockets 98in the escutcheon member 36. Conversely, the escutcheon member 36includes two diametrically opposed, longitudinally extending posts 100capable of being plugged into complementary sockets 102 in theescutcheon member 34, the posts and sockets 100 and 102 being angularlydisplaced from the posts and sockets 96 and 98 by 90. These posts andsockets are formed integrally with certain of the aforementioned radialwebs interconnecting the hub and skirt 88 and 92 of the escutcheonmember 34 and the hub and skirt and 94 of the escutcheon member 96.

integral with the inner ends of the hubs 88 and 90 are central bosses104 and 106 coaxial with the knob axis 38. The connecting means 40comprises a single screw 108 coaxial with the knob axis 38 andinterconnecting the two bosses 104 and 106. More particularly, the screw108 has a head seated against the boss 104 on the hub 88 of theescutcheon member 34, and is threaded into the boss 106 on the hub 90 ofthe escutcheon member 36. Preferably, the screw 108 is a selftappingscrew capable of forming its own threads in the bosses 104 and 106.

As will be apparent, the single screw 108 forms the sole interconnectingmeans between the escutcheon members 34 and 36 so that these members canbe interconnected very quickly and easily, which is an importantfeature. The screw 108 may be driven after the knob 44 is mounted on theescutcheon member 34, but before an end cap 154 forming part of the knob44 and described hereinafter is installed.

it will be noted that the inner end of the latchbolt 50 is provided witha longitudinal slot 110 into which the inner ends of the central bosses104 and 106 on the escutcheon members 34 and 36 project. Thisrelationship assists in properly positioning relative to each other theescutcheon members 4 and 36 and the assembly comprising the latchbolthousing 48 and the latchbolt 50.

The escutcheon-member skirts 92 and 94 are provided with diametricallyopposed notches 112 and 114. The inner end of the latchbolt housing 48is receivable in one of the notches 112 and the corresponding notch 114,depending on whether the door 22 is a left-hand or a right-hand door.The latchbolt housing 48 and the edges of the pair of notches 112 and114 in which it is disposed constitute a means for interlocking thelatchbolt housing and the escutcheon members 34 and 36 so that thesingle screw 108 holds the escutcheon members and the latchbolt housingin assembled relation, which is an important feature of the invention.

Considering this interlocking means in more detail, it includes edges ofthe notches 112 and 114 insertable in diametrically opposed grooves 116formed in the latchbolt housing 48 and paralleling the knob axis 38.This interlocking means also includes, as shown in FIG. 2, prongs 118and 120 respectively forming parts of the escutcheon-member skirts 92and 94 and respectively insertable into diametrically opposed,complementary holes 122 in the latchbolt housing 48. With thisinterlocking means, the escutcheon members 34 and 36 and the latchbolthousing 48 are precisely positioned relative to each other and aresecured in the correct relative positions by the single screw 108coaxial with the knob axis 38.

The knobs 44 and 46 are hollow and include integral tubular shafts 124and 126 respectively journalled in the hubs 88 and 90 of the escutcheonmembers 34 and 36. The shafts 124 and 126 are provided on one sidethereof with aligned ribs 128 and 130 having therein bores parallelingthe knob axis 38 and receiving therein the ends of thelatchbolt-retracting pin 80. The ribs 128 and 130 terminate at theirinner ends in integral, shouldered, flexible latching tongues 134 and136 respectively inserted into arcuate openings 138 and 140 in theescutcheon members 34 and 36, which openings limit the angular throws ofthe knobs 44 and 46. The shoulders on the latching tongues 134 and 136are respectively engageable with shoulders 144 and 146 on the escutcheonmembers 34 and 36 to prevent axial disengagement of the knobs 44 and 46from the escutcheon members 34 and 36. The latching tongues 134 and 136respectively cooperate with the shoulders 144 and 146 to providesnap-acting latching means for automatically latching the knobs 44 and46 in place when they are displaced axially inwardly relative to therespective escutcheon members 34 and 36.

As will be apparent, the knobs 44 and 46 can be assembled with therespective escutcheon members 34 and 36 very simply by merely displacingthe knobs axially inwardly relative to the respective escutcheon membersuntil the flexible latching tongues 134 and 136 respectively snap behindthe corresponding shoulders 144 and 146 on the escutcheon members 34 and36.

One end of the latchbolt-retracting pin 80 is driven into the bore inthe rib 128 of the knob 44 with a press fit. ln assembling the twoknob-escutcheon combinations, the other end of the latchbolt-retractingpin 80 is inserted into the bore in the rib 130 of the knob 46, in whichit has a sliding fit, as the two knob-escutcheon combinations areinserted into opposite ends of the opening 24 through the door 22. Atthe same time, the two escutcheon members 34 and 36 are interlocked withthe latchbolt housing 48 in the manner hereinbefore discussed. Thesubsequent driving of the single screw 108 then interlocks all of thesecomponents, viz., the two escutcheon members 34 and '36 and thelatchbolt housing 48.

It will be noted that, since the latchbolt-retracting pin 80 extendslongitudinally through the ribs 128 and 130, and the latching tongues134 and 136 forming inward extensions of these ribs, the pin rigidifiesthe flexible latching tongues, after assembly, so that the knobs 44 and46 cannot be detached from the corresponding escutcheon members 34 and36 by pulling outwardly thereon. In other words, once the com ponents ofthe door lock have been assembled, as shown in the drawings, thelatchbolt-retracting pin 80 keeps the latching tongues 134 and 136 fromflexing inwardly so that they cannot become disengaged from thecorresponding shoulders 144 and 146 on the escutcheon members 34 and 36.It will be noted that the latchbolt-retracting pin 80 is fixedlyconnected to the knob 44, but is axially movable relative to the otherknob 46. This relationship enters into the mode of operation of alocking means to be described hereinafter.

After the two knob-escutcheon combinations and the latchbolt housing 48have been assembled and secured together by driving the screw 108, theouter end of the knob 44 may be closed by snapping thereinto the end cap154, the knob 44 being provided therein with an internal annular groovefor the purpose. Similarly, the outer end of the other knob 46 may beclosed by snapping thereinto an end cap 156. The end cap 154 isimperforate, but the end cap 156 has a central opening 158 for theadmission of a suitable tool 160 for emergency unlocking of a lockingmeans which will now be described.

To achieve privacy, the door lock 20 is adapted to be locked from theinside by axially displacing the knob 44 inwardly, i.e., toward the door22, until a detent 162 on the tubular shaft 124 of the knob 44 snapsinto a complementary recess in the outer end of the hub 88 of thecorresponding escutcheon member 34, as shown in FIG. 8. (Similar axiallyinward movement of the outside knob 46 is prevented by a tab 164, FIGS.2 and 9, on the escutcheon member 36. Originally, the two escutcheonmembers were identical, and a similar tab was broken off the escutcheonmember 34 to permit axially inward, locking movement of the inside knob44.)

A locking means on the inside knob 44 and its escutcheon member 34responds to axially inward movement of this knob into its lockingposition to lock both knobs 44 and 46, through the latchbolt-retractingpin 80, against rotation so as to prevent retraction of the latchbolt50. This locking means comprises notches 166 which are formed in theinner end of the tubular shaft 124 of the knob 44 and which are adaptedto receive therein complementary radial webs 168 formed at the inner endof the hub 88 of the escutcheon member 34. When this occurs as theresult of axially inward displacement of the knob 44 toward the door 22,both knobs 44 and 46 are locked against rotation to prevent retractionof the latchbolt 50. The interlocking of the notches 166 and the webs168 is visible in FIGS, 8 and 9 of the drawings.

As will be evident from a comparison of FIGS. 4 and 8, axially inward,locking displacement of the inside knob 44 toward the door 22 results inaxially outward projection of the right end of the latchbolt-retractingpin 80 beyond the axially outer end of the rib 130 of the tubular shaft126 of the outside knob 46. This condition is shown in FIG. 8 of thedrawings. An emergency release button 170 is disposed in and is movableaxially of the tubular shaft 126 of the outside knob 46, and is providedwith an external annular flange 172 engageable with the axiallyprojecting end of the latchbolt-retracting pin 80. The emergencyunlocking tool 160, which may be anything available of a size to beadmitted by the opening 158, is seatable in a central recess in theouter end of the emergency release button 170.

As will be apparent, with the tool 160 inserted as shown in FIG. 8, itcan e displaced axially inwardly toward the door 22 to displace theemergency release button 170 axially inwardly, and to concurrentlydisplace the latchbolt-retracting pin to the left. This pin, beingrigidly connected to the inside knob 44, displaces it axially outwardlyaway from the door 22 into its unlocked position, wherein the notches166 are clear of the webs 168. Only a relatively small force applied tothe tool is required to overcome the detent 162 tending to retain theinside knob 44 in its locked position.

The door lock 20 is also provided with a cam means for preventingaccidental locking if the door 22 is closed inadvertently with theinside knob 44 in its locking position. More particularly, thelatchbolt-retracting pin 80 has secured thereon a collar provided with afrustoconical cam 176, FIGS. 4, 8 and 9, which, as best shown in FIG. 9,is receivable in a notch 178 in the latchbolt 50 when the knob 44 is inits locking position. If the door 22 is inadvertently closed under suchconditions, a cam surface 180 forming one wall of the notch 178 acts onthe frustoconical cam 176, as the latchbolt 50 is retracted uponengaging the latch-plate-striker portion 66, to move the knob 44outwardly into its nonlocking position, Thus, accidental locking isprevented. To permit this cam means to function if the latchbolt housing48 is installed 180 from the position shown, to accommodate a door whichopens outwardly, the opposite side of the latchbolt S0 is provided witha symmetrical cam notch.

The door lock 20 may be converted to a simple door latch by leaving inplace the tab on the escutcheon member 34 corresponding to the tab 164on the escutcheon member 36, thereby preventing axially inwarddisplacement of the knob 44 toward the door 22. Also, the button may beomitted and the end cap 156 replaced by an imperforate one.

Preferably, with the exception of such parts as the latchbolt spring 70,the latchbolt-retracting pin 80 and the single interconnecting screw108, all components of the door lock 20 are made of suitable plasticmaterials. Such exposed parts as the escutcheon members 34 and 36 andthe knobs 44 and 46 may be made of a plastic material capable ofaccepting metal-simulating finishes. Also, this plastic material musthave the degree of flexibility necessary to permit snapping the latchingtongues 134 and 136 and the locking detent 162 into place. Examples ofsuitable plastic materials are nylon, various styrene polymers andcopolymers, and the like.

Although an exemplary embodiment of the invention has been disclosedherein for purposes of illustration, it will be understood that variouschanges, modifications, and substitutions may be incorporated in thisembodiment.

I claim as my invention:

1. In a door latch to be mounted on a door having an openingtherethrough adjacent one edge and having a hole in such edge into theopening, the combination of:

a. two escutcheon members respectively insertable into and adapted tooverlie the ends of the opening through the door and providing a knobaxis;

b. a single connecting means coaxial with said knob axis forinterconnecting said escutcheon members;

c. a latchbolt housing containing a latchbolt and insertable into thehole in the door edge;

d. two knobs respectively mounted on said escutcheon members forrotation about said knob axis;

e. means connected to said knobs for retracting said latchbolt; and

f. said latchbolt having an elongated opening through which said singleconnecting means extends.

2. A door latch as defined in claim 1 wherein said connecting meanscomprises a single screw coaxial with said knob axis and carried by oneof said escutcheon members and threadable into the other.

3. A door latch according to claim 2 wherein said escutcheon members areprovided with central bosses coaxial with said knob axis and facing eachother and through which said screw extends, said latchbolt having a slotreceiving said facing bosses therein.

4. A door latch as set forth in claim 2 including interengageable meanson said escutcheon members and said latchbolt housing for interlockingsame so that said single screw holds said escutcheon members and saidlatchbolt housing in assembled relation.

5. A door latch according to claim 1 for use with a doorjamb having acavity aligned with the hole in the door edge when the door is closed,including a latch plate driven into said cavity with no separatesecuring means. I

6. In a door latch to be mounted on a door having an openingtherethrough adjacent one edge and having a hole in such edge into theopening, the combination of:

a two escutcheon members respectively insertable into and adapted tooverlie the ends of the opening through the door and providing a knobaxis;

b. means for interconnecting said escutcheon members;

c. a latchbolt housing containing a latchbolt and insertable into thehole in the door edge;

d. two knobs respectively mounted on said escutcheon members forrotation about said knob axis;

e. means connected to said knobs for retracting said latchbolt;

f. snap-acting latching means integral with said escutcheon members andsaid knobs for rotatably connecting said knobs to said escutcheonmembers;

g. said snap-acting latching means including integral, shouldered,flexible latching tongues on said knobs paralleling said knob axis andengageable with complementary, integral shoulders on said escutcheonmembers; and

h. said latchbolt-retracting means including a pin paralleling said knobaxis and extending through a closely fitting bore in one latching tongueof each of said knobs thus rigidifying these latching tongues.

7. In a door latch to be mounted on a door having an openingtherethrough adjacent one edge and having a hole in such edge into theopening, the combination of:

a. two escutcheon members respectively insertable into and adapted tooverlie the ends of the opening through the door and providing a knobaxis;

b. means for interconnecting said escutcheon members;

0. a latchbolt housing containing a latchbolt and insertable into thehole in the door edge;

d. two knobs respectively mounted on said escutcheon members forrotation about said knob axis;

e. means interconnecting said knobs for retracting said latchbolt,comprising a pin parallel to and spaced from said knob axis;

f. locking means responsive to movement of one of said knobs toward theother along said knob axis from a nonlocking position to a lockingposition;

g. said pin being rigidly connected to said one knob and beinglongitudinally slidable relative to the other; and

h. means for displacing said pin longitudinally thereof in a directionto cause it to move said one knob into its nonlocking position.

I 8. A door latch according to claim 7 wherein said unlocking meanscomprises cam means on said latchbolt and said pin and responsive toretraction of said latchbolt.

1. In a door latch to be mounted on a door having an openingtherethrough adjacent one edge and having a hole in such edge into theopening, the combination of: a. two escutcheon members respectivelyinsertable into and adapted to overlie the ends of the opening throughthe door and providing a knob axis; b. a single connecting means coaxialwith said knob axis for interconnecting said escutcheon members; c. alatchbolt housing containing a latchbolt and insertable into the hole inthe door edge; d. two knobs respectively mounted on said escutcheonmembers for rotation about said knob axis; e. means connected to saidknobs for retracting said latchbolt; and f. said latchbolt having anelongated opening through which said single connecting means extends. 2.A door latch as defined in claim 1 wherein said connecting meanscomprises a single screw coaxial with said knob axis and carried by oneof said escutcheon members and threadable into the other.
 3. A doorlatch according to claim 2 wherein said escutcheon members are providedwith central bosses coaxial with said knob axis and facing each otherand through which said screw extends, said latchbolt having a slotreceiving said facing bosses therein.
 4. A door latch as set forth inclaim 2 including interengageable means on said escutcheon members andsaid latchbolt housing for interlocking same so that said single screwholds said escutcheon members and said latchbolt housing in assembledrelation.
 5. A door latch according to claim 1 for use with a doorjambhaving a cavity aligned with the hole in the door edge when the door isclosed, including a latch plate driven into said cavity with no separatesecuring means.
 6. In a door latch to be mounted on a door having anopening therethrough adjacent one edge and having a hole in such edgeinto the opening, the combination of: a. two escutcheon membersrespectively insertable into and adapted to overlie the ends of theopening through the door and providing a knob axis; b. means forinterconnecting said escutcheon members; c. a latchbolt housingcontaining a latchbolt and insertable into the hole in the door edge; d.two knobs respectively mounted on said esCutcheon members for rotationabout said knob axis; e. means connected to said knobs for retractingsaid latchbolt; f. snap-acting latching means integral with saidescutcheon members and said knobs for rotatably connecting said knobs tosaid escutcheon members; g. said snap-acting latching means includingintegral, shouldered, flexible latching tongues on said knobsparalleling said knob axis and engageable with complementary, integralshoulders on said escutcheon members; and h. said latchbolt-retractingmeans including a pin paralleling said knob axis and extending through aclosely fitting bore in one latching tongue of each of said knobs thusrigidifying these latching tongues.
 7. In a door latch to be mounted ona door having an opening therethrough adjacent one edge and having ahole in such edge into the opening, the combination of: a. twoescutcheon members respectively insertable into and adapted to overliethe ends of the opening through the door and providing a knob axis; b.means for interconnecting said escutcheon members; c. a latchbolthousing containing a latchbolt and insertable into the hole in the dooredge; d. two knobs respectively mounted on said escutcheon members forrotation about said knob axis; e. means interconnecting said knobs forretracting said latchbolt, comprising a pin parallel to and spaced fromsaid knob axis; f. locking means responsive to movement of one of saidknobs toward the other along said knob axis from a nonlocking positionto a locking position; g. said pin being rigidly connected to said oneknob and being longitudinally slidable relative to the other; and h.means for displacing said pin longitudinally thereof in a direction tocause it to move said one knob into its nonlocking position.
 8. A doorlatch according to claim 7 wherein said unlocking means comprises cammeans on said latchbolt and said pin and responsive to retraction ofsaid latchbolt.